Laboratory fume hoods often do not adequately provide protection to a chemist or technician at the hood. The reason for failure of the hoods to perform adequately are varied and, in many instances, difficult to determine.

In some cases, the laboratory hood manufacturer has provided equipment that does not reflect the state oF art in controlling laboratory exposures. In other cases, the architect or engineer has disregarded the function of the hood thus the design of the installation is faulty and the hood will not work. The contractor may have installed the system so poorly that it will not adequately function. Finally, the chemist or technician may misuse the hood, causing poor performance.

This paper considers a method of evaluating the performance of laboratory fume hoods. Using the method, the paper examines several instances where the laboratory fume hood performed inadequately, quantifies the performance and identifies the cause of poor performance.

Units: SI